Substrate transporter and substrate transport method

ABSTRACT

In a substrate transporter, a carry-in-and-out mechanism transports a substrate placed in a horizontal posture. A notch aligner rotates a substrate in a circumferential direction to change a circumferential position of a notch. The carry-in-and-out mechanism includes four supporters that oppose a lower surface of the peripheral portion of the substrate. In the substrate transporter, a controller controls the notch aligner on the basis of warpage-and-notch-position information and input information that is input about the warped state of the substrate, to determine the circumferential position of the notch of the substrate. Thus, the lower surface of the substrate placed on the transport mechanism comes into contact with the four supporters of the transport mechanism. As a result, it is possible to prevent or suppress the occurrence of rattling or misalignment of the substrate during transport by the transport mechanism, and enables stable transport of the substrate.

TECHNICAL FIELD

The present invention relates to a technique for transportingsubstrates.

BACKGROUND ART

Substrate processing apparatuses that perform various types ofprocessing on substrates have conventionally been used in the process ofmanufacturing semiconductor substrates (hereinafter, simply referred toas “substrates”). For example, Japanese Patent Application Laid-Open No.2010-93230 (Document 1) discloses a batch-type substrate processingapparatus that processes a plurality of substrates by one operation. Inthis substrate processing apparatus, a plurality of substrates alignedalong the thickness (hereinafter, referred to as a “thicknessdirection”) of the substrates in a horizontal posture are held andtransported by a batch hand. This substrate processing apparatusincludes a substrate-direction alignment mechanism for aligning thedirections of a plurality of substrates that are held in a verticalposture by a chuck. The substrate-direction alignment mechanism aligns aplurality of substrates at once so that the orientations (i.e.,circumferential positions) of notches provided in peripheral portions ofthe substrates match one another.

A substrate processing apparatus disclosed in Japanese PatentApplication Laid-Open No. 2013-258312 (Document 2) includes a notchalignment device that aligns the positions of notches by individuallypicking up substrates one at a time. This substrate processing apparatusdetermines the destination to which the substrates are transported by arobot, on the basis of information such as notch alignment progressinformation that indicates whether notch alignment is completed, andprocessing progress information that indicates whether processing to beperformed on substrates is completed.

Meanwhile, a substrate inspection device disclosed in Japanese PatentApplication Laid-Open No. 2006-339574 (Document 3) includes a transportarm that transports a wafer while adsorbing the lower surface of thewafer under vacuum. If the wafer is warped, in order to preventmisdetection of imperfect wafer adsorption by the transport arm, thesubstrate inspection apparatus changes a threshold value for vacuumpressure in accordance with the amount of warp in the wafer, thethreshold value being used to judge the imperfect adsorption. If theadsorptive activity of the transport arm decreases due to a change inthe threshold value, the wafer transport speed is reduced in order toprevent the wafer to be displaced during transport.

When substrates in a horizontal posture are supported from the undersideby a batch hand without being adsorbed as in the substrate processingapparatus in Document 1 and if these substrates are warped, thesubstrates may rattle (e.g., may shake or be displaced in the directionof transport), and this makes it difficult to stably support andtransport the substrates.

SUMMARY OF INVENTION

The present invention is intended for a substrate transporter, and it isan object of the present invention to stably transport substrates. Thepresent invention is also intended for a substrate transport method.

A substrate transporter according to the present invention includes atransport mechanism for transporting a substrate that is placed in ahorizontal posture, a notch-position changing mechanism for rotating thesubstrate that is to be placed on the transport mechanism, in acircumferential direction to change a position in the circumferentialdirection of a notch that is provided in a peripheral portion of thesubstrate, a storage for storing warpage-and-notch-position informationthat includes a plurality of combinations of a warped state of thesubstrate and a notch position at which the substrate in the warpedstate is held in a proper posture when placed on the transportmechanism, and a controller for controlling the notch-position changingmechanism. The transport mechanism includes four supporters that opposea lower surface of the peripheral portion of the substrate. The lowersurface of the substrate that is placed on the transport mechanism andthe four supporters of the transport mechanism are brought into contactwith each other by the controller controlling the notch-positionchanging mechanism on the basis of the warpage-and-notch-positioninformation and input information that is input about the warped stateof the substrate to determine the position in the circumferentialdirection of the notch of the substrate. This substrate transporter iscapable of stably transporting substrates.

In a preferred embodiment of the present invention, the transportmechanism includes two hand elements, on each of which two supportersamong the four supporters are provided, and the substrate that is placedon the transport mechanism is convex upward between the two supportersof each hand element and vertically upward of each hand element.

In another preferred embodiment of the present invention, the transportmechanism transports another substrate along with the substrate, thenotch-position changing mechanism rotates the another substrate and thesubstrate either sequentially or simultaneously in the circumferentialdirection to determine a position in the circumferential direction of anotch that is provided in a peripheral portion of the another substrate,in the same manner as in the case of the substrate, the transportmechanism includes another four supporters that oppose a lower surfaceof the peripheral portion of the another substrate, and the lowersurface of the another substrate that is placed on the transportmechanism comes into contact with the another four supporters of thetransport mechanism.

Another substrate transporter according to the present inventionincludes a transport mechanism for transporting a substrate that isplaced in a horizontal posture, and a controller for controlling thetransport mechanism on the basis of a warped state of the substrate tocontrol acceleration at a time of starting and stopping movement of thetransport mechanism. This substrate transporter is capable of stablytransporting substrates.

In the aforementioned substrate transporter, for example, the substrateis curved in a first radial direction to one side in a thicknessdirection of the substrate with a first curvature, and the substrate iscurved in a second radial direction orthogonal to the first radialdirection to the one side in the thickness direction with a secondcurvature greater than the first curvature.

In the aforementioned substrate transporter, for example, the substrateis curved in a first radial direction to one side in a thicknessdirection of the substrate, and the substrate is curved in a secondradial direction orthogonal to the first radial direction to the otherside in the thickness direction.

These and other objects, features, aspects and advantages of the presentinvention will become more apparent from the following detaileddescription of the present invention when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view of a substrate processing apparatus according toan embodiment;

FIG. 2 is a plan view of part of the substrate processing apparatus;

FIG. 3 is a side view of part of the substrate processing apparatus;

FIG. 4 is a perspective view of a substrate;

FIG. 5 is a perspective view of a substrate;

FIG. 6 is a side view of a carry-in-and-out mechanism;

FIG. 7 is a plan view of a batch hand and a substrate;

FIG. 8 is a flowchart illustrating a procedure for aligning andtransporting substrates;

FIG. 9 is a cross-sectional view of substrates held in a horizontalposture;

FIG. 10 is a cross-sectional view of the substrates held in a horizontalposture;

FIG. 11 is a cross-sectional view of a substrate held in a horizontalposture; and

FIG. 12 is a flowchart illustrating a procedure for transportingsubstrates.

DESCRIPTION OF EMBODIMENTS

FIG. 1 is a plan view of a substrate processing apparatus 10 accordingto an embodiment of the present invention. The substrate processingapparatus 10 has an approximately rectangular shape in plan view. Thesubstrate processing apparatus 10 is a batch-type substrate processingapparatus that processes a plurality of semiconductor substrates 9(hereinafter, simply referred to as “substrates 9”) by one operation.The substrates 9 are approximately disc-like substrates. Each substrate9 has a notch 93 (see FIGS. 4 and 5) indicating a crystal orientation ina peripheral portion. The notch 93 has a depth of approximately 1 mmfrom the outer periphery of the substrate 9.

The substrate processing apparatus 10 includes a FOUP holder 1, asubstrate processing part 2, a main transport mechanism 3, acarry-in-and-out mechanism 4, a posture changing mechanism 5, a pusher6, a delivery mechanism 7, a stocker 200, a controller 100, and astorage 101. The controller 100 controls operations or other activitiesof each constituent element of the substrate processing apparatus 10.The controller 100 is a general computer system that includes, forexample, a CPU for performing various types of computations, a ROM forstoring basic programs, and a RAM for storing various types ofinformation. The FOUP holder 1 is disposed adjacent to thecarry-in-and-out mechanism 4. The FOUP holder 1 holds a FOUP 95. TheFOUP 95 is a container that houses a plurality of (e.g., 25) substrates9 in a horizontal posture, with the substrates 9 being stacked in the Zdirection.

The Z direction in FIG. 1 is a direction parallel to the direction ofgravity, and is also referred to as an “up-down direction.” The Xdirection in FIG. 1 is a direction perpendicular to the Z direction. TheY direction is a direction perpendicular to the X and Y directions. Ahorizontal posture of the substrates 9 refers to a posture in which thedirection of the normal to the main surfaces of the substrates 9 pointsin approximately the Z direction. A vertical posture of the substrates9, which will be described later, refers to a posture in which thedirection of the normal to the main surfaces of the substrates 9 pointsin a direction approximately perpendicular to the Z direction. In thesubstrate processing apparatus 10, a plurality of substrates 9 arestacked in either a horizontal or vertical posture in a directionapproximately perpendicular to the main surfaces of the substrates 9. Inother words, the plurality of substrates 9 in a horizontal or verticalposture are aligned in the thickness direction of the substrates 9.

The stocker 200 is disposed on the −Y side of and adjacent to the FOUPholder 1. The stocker 200 includes a FOUP stock part 201, a FOUPplacement area 202, a notch aligner 203, a substrate transport robot204, a FOUP holder 205, a first FOUP transfer robot 206, and a secondFOUP transfer robot 207. The FOUP stock part 201 supports a plurality ofFOUPs 95, which are arranged two-dimensionally in X and Y directions,from the underside. The FOUPs 95 are to be placed on the FOUP placementarea 202.

The notch aligner 203 carries out notch alignment, which will bedescribed later, by rotating a substrate 9 held in a horizontal posturein a circumferential direction. In other words, the notch aligner 203changes the circumferential orientation of a substrate 9 by rotating thesubstrate 9 in the circumferential direction, and determines thecircumferential position of the substrate 9. The notch aligner 203includes a substrate supporter 203 c, a motor 203 a, and a notchposition sensor 203 b. The substrate supporter 203 c rotatably supportsa substrate 9 held in a horizontal posture. The motor 203 a is a rotatorthat rotates a substrate 9 along with the substrate supporter 203 c. Thenotch position sensor 203 b acquires the angular position of a rotatingsubstrate 9 (i.e., circumferential orientation of the substrate 9) byoptically detecting the notch 93 (see FIGS. 4 and 5) of the substrate 9supported by the substrate supporter 203 c.

The substrate transport robot 204 transports substrates 9 one at a timebetween the FOUP 95 placed on the FOUP placement area 202 and the notchaligner 203. The FOUP holder 205 holds a FOUP 95 that is to be conveyedinto the internal space of the stocker 200. The first FOUP transferrobot 206 transfers a FOUP 95 to and from the FOUP stock part 201, theFOUP placement area 202, and the FOUP holder 205. The second FOUPtransfer robot 207 transfers a FOUP 95 to and from the FOUP stock part201, the FOUP placement area 202, and the FOUP holder 1. Note that onlythe paths of travel of the first FOUP transfer robot 206 and the secondFOUP transfer robot 207 are illustrated in schematic form in FIG. 1.

In the stocker 200, when a new FOUP 95 is placed on the FOUP placementarea 202, the first FOUP transfer robot 206 transports this FOUP 95 tothe FOUP stock part 201. The second FOUP transfer robot 207 moves a newFOUP 95 that holds unprocessed substrates 9 from the FOUP stock part 201to the FOUP holder 1 in accordance with a schedule of processingperformed by the substrate processing apparatus 10. The second FOUPtransfer robot 207 also moves a FOUP 95 that has undergone processingperformed by the substrate processing apparatus 10 from the FOUP holder1 to the FOUP stock part 201.

The substrate transport robot 204 includes an arm 204 a, an arm drivemechanism 204 b, and substrate abutment parts 204 c. The arm drivemechanism 204 b rotates, extends, and contracts the arm 204 a. Thesubstrate abutment parts 204 c are provided on the arm 204 a and supporta substrate 9 in point contact with the lower surface of the substrate9. The upper surface of the arm 204 a has three substrate abutment parts204.

The substrate transport robot 204 rotates, extends, and contracts thearm 204 a, takes a single substrate 9 out of the FOUP 95 that is placedon the FOUP placement area 202, and turns in the X direction to face thenotch aligner 203. The substrate transport robot 204 then elongates thearm 204 a and places the taken-out substrate 9 on the substratesupporter 203 c of the notch aligner 203.

In the notch aligner 203, the motor 203 a rotates the substrate 9supported by the substrate supporter 203 c in the circumferentialdirection to change the circumferential orientation of the substrate 9.Then, the notch position sensor 203 b detects the notch 93 of therotating substrate 9, and the motor 203 a is stopped with predeterminedtiming after the detection (i.e., after the elapse of a predeterminedperiod of time since the detection of the notch 93). Note that thepredetermined period of time may be zero. In this way, the rotation ofthe substrate 9 is stopped when the notch 93 of the substrate 9 islocated at a predetermined position. That is, the notch 93 of thesubstrate 9 is aligned in the circumferential direction. The notchaligner 203 is a notch-position changing mechanism for changing thecircumferential position of the notch 93 of the substrate 9.

When the notch aligner 203 has determined the circumferential positionof the substrate 9, the substrate 9 is transported out of the notchaligner 203 by the substrate transport robot 204 and returned to theFOUP 95 placed on the FOUP placement area 202. Subsequently, in the samemanner, the next substrate 9 is taken out of the FOUP 95 placed on theFOUP placement area 202 and then returned to the FOUP 95 after the notchaligner 203 has determined the circumferential position of the substrate9 (i.e., the notch 93 is aligned in the circumferential direction). Byrepeating this operation for all of the substrates 9 in the FOUP 95, thecircumferential orientations of the plurality of substrates 9 in theFOUP 95 are changed, and the circumferential positions of the substrates9 are determined. In other words, these substrates 9 are aligned in thecircumferential direction. The FOUP 95 for which the substrates 9 housedtherein have been aligned in the circumferential direction istransported to the FOUP holder 1 by the second FOUP transfer robot 207.

FIG. 2 is an enlarged plan view of part of the substrate processingapparatus 10. FIG. 3 is a side view of part of the substrate processingapparatus 10. In the substrate processing apparatus 10, thecarry-in-and-out mechanism 4 is disposed on the +Y side of the FOUPholder 1 and opposes the FOUP holder 1 in the Y direction as illustratedin FIG. 2. The FOUP holder 1 is not shown in FIG. 3.

As illustrated in FIGS. 2 and 3, the posture changing mechanism 5 isdisposed on the +X side of the carry-in-and-out mechanism 4. The pusher6 is disposed on the +X side of the posture changing mechanism 5. Thedelivery mechanism 7 and the main transport mechanism 3 are disposed onthe +X side of the pusher 6. In the state illustrated in FIG. 3, themain transport mechanism 3 is located on the +Z side of (i.e., above)the delivery mechanism 7. The substrate processing part 2 is disposed onthe +Y side of the main transport mechanism 3 as illustrated in FIG. 1.

The substrate processing part 2 includes a first liquid chemical tank21, a first rinsing liquid tank 22, a second liquid chemical tank 23, asecond rinsing liquid tank 24, a dry processing part 25, a first lifter27, and a second lifter 28. The first liquid chemical tank 21, the firstrinsing liquid tank 22, the second liquid chemical tank 23, the secondrinsing liquid tank 24, and the dry processing part 25 are aligned inthe Y direction from the +Y side to the −Y side in the specified order.The first liquid chemical tank 21 and the second liquid chemical tank 23retain liquid chemicals of the same type or different types. The firstrinsing liquid tank 22 and the second rinsing liquid tank 24 each retaina rinsing liquid (e.g., deionized water).

When the substrate processing apparatus 10 processes substrates 9,first, a plurality of (e.g., 25) substrates 9 housed in a horizontalposture in the FOUP 95 placed on the FOUP holder 1 are held by a batchhand 41 of the carry-in-and-out mechanism 4 illustrated in FIGS. 2 and 3and conveyed out of the FOUP 95. The batch hand 41 collectively holds aplurality of substrates 9 that are aligned in the Z direction in ahorizontal posture. The carry-in-and-out mechanism 4 also includes asingle-substrate hand 42 that holds a single substrate 9 in a horizontalposture.

Then, the batch hand 41 rotates horizontally and moves ahead toward theposture changing mechanism 5 so that the plurality of substrates 9 aretransferred from the carry-in-and-out mechanism 4 to the posturechanging mechanism 5. The posture changing mechanism 5 collectivelyholds the plurality of substrates 9, which are stacked in the Zdirection in a horizontal posture, with a horizontal holder 51. Theposture changing mechanism 5 causes a holder rotation mechanism 54 torotate the plurality of substrates 9 by 90 degrees in thecounterclockwise direction in FIG. 3 about a rotational shaft 541pointing in the Y direction, along with the horizontal holder 51, avertical holder 52, and a mounting block 53. This rotation changes theposture of the substrates 9 at once from horizontal to vertical. Thesubstrates 9 in a vertical posture are collectively held by the verticalholder 52.

Then, an up-and-down holder 61 is moved upward by driving a holderelevating mechanism 62 of the pusher 6, and receives and holds thesubstrates 9 from the vertical holder 52 indicated by the dasheddouble-dotted line in FIG. 3. That is, the substrates 9 held in avertical posture are transferred between the vertical holder 52 and thepusher 6. The up-and-down holder 61 collectively holds the substrates 9that are aligned (i.e., stacked) in approximately the X direction in avertical posture. When the horizontal holder 51 and the vertical holder52 of the posture changing mechanism 5 are rotated by 90 degrees in theclockwise direction in FIG. 3 and retracted from above the holderelevating mechanism 62, the up-and-down holder 61 is rotatedhorizontally by 180 degrees about a rotational shaft 63 pointing in theZ direction and then moved down by the holder elevating mechanism 62.Accordingly, the positions in the stacking direction of the substrates 9are shifted by a half of the pitch of the substrates 9 (i.e., a half ofthe distance in the stacking direction between two adjacent substrates9, which is hereinafter referred to as a “half pitch”) from thepositions before the rotation.

Thereafter, in the same procedure as described above, a new plurality of(e.g., 25) substrates 9 housed in the FOUP 95 on the FOUP holder 1 aretransferred from the carry-in-and-out mechanism 4 to the posturechanging mechanism 5. The posture changing mechanism 5 collectivelychanges the posture of the new substrates 9 from horizontal to vertical.Then, the up-and-down holder 61 of the pusher 6 is again moved upwardand receives and holds the new substrates 9 from the posture changingmechanism 5. At this time, the substrates 9 already held by theup-and-down holder 61 (hereinafter, referred to as a “first substrategroup”) are inserted among the new substrates 9 (hereinafter, referredto as a “second substrate group”) from the underside. In this way, theposture changing mechanism 5 and the pusher 6 carry out batch assemblyin which a batch is formed by combining the first substrate group andthe second substrate group.

As described above, the substrates 9 (hereinafter, also referred to as“first substrates 9”) in the first substrate group are rotated by 180degrees (i.e., turned around) before insertion into the second substrategroup. Thus, each of the first substrates 9 in the first substrate groupis disposed between each pair of the substrates 9 (hereinafter, alsoreferred to as “second substrates 9”) in the second substrate group,with the first substrates 9 and the second substrates 9 alternatelyarranged front-to-front and back-to-back. In other words, each pair ofadjacent substrates 9 among the plurality of (e.g., 50) substrates 9held by the up-and-down holder 61 are disposed such that their frontsurfaces or their rear surfaces face each other (i.e., they are in aface-to-face situation). The front surfaces of the substrates 9 may bemain surfaces where circuit patterns are formed, and the rear surfacesof the substrates 9 may be main surfaces on the side opposite to thefront surfaces.

Alternatively, when the up-and-down holder 61 that holds the firstsubstrate group is moved only horizontally by the half pitch in thealignment direction of the substrates 9 without being rotated by 180degrees before receipt of the second substrate group, the pusher 6 maycarry out batch assembly in a state in which each pair of adjacentsubstrates 9 is disposed such that their front and rear surfaces faceeach other (i.e., they are in a face-to-back situation).

The substrates 9 assembled into a batch on the up-and-down holder 61 aretransferred from the up-and-down holder 61 to a carry-in chuck 71 of thedelivery mechanism 7. The carry-in chuck 71 moves in the +X directionfrom above the holder elevating mechanism 62 while holding the receivedsubstrates 9 in a vertical posture. Subsequently, an intermediate chuck72 of the delivery mechanism 7 moves downward to receive the substrates9 from the carry-in chuck 71 and then moves upward. Then, a substratechuck 31 of the main transport mechanism 3 receives the substrates 9from the intermediate chuck 72. The substrate chuck 31 holds thesubstrates 9 that are aligned in the X direction in a vertical posture.

The main transport mechanism 3 transports the unprocessed substrates 9held by the substrate chuck 31 in the +Y direction and positions thesubstrates 9 above the first lifter 27 of the substrate processing part2 illustrated in FIG. 1. The first lifter 27 collectively receives thesubstrates 9, which are aligned in the X direction in a verticalposture, from the substrate chuck 31. The first lifter 27 moves thesubstrates 9 down into the first liquid chemical tank 21 andcollectively immerses the substrates 9 in the liquid chemical retainedin the first liquid chemical tank 21. Immersing the substrates 9 in theliquid chemical for a predetermined period of time completes liquidchemical processing performed on the substrates 9.

The first lifter 27 then pulls the substrates 9 up out of the firstliquid chemical tank 21 and moves in the −Y direction. The first lifter27 moves the substrates 9 down into the first rinsing liquid tank 22 andcollectively immerses the substrates 9 in the rinsing liquid retained inthe first rinsing liquid tank 22. Immersing the substrates 9 in therinsing liquid for a predetermined period of time completes rinsingprocessing performed on the substrates 9. After the rinsing processinghas completed, the first lifter 27 pulls the substrates 9 up out of thefirst rinsing liquid tank 22. The substrate chuck 31 of the maintransport mechanism 3 collectively receives the substrates 9 from thefirst lifter 27 and moves to above the second lifter 28.

Like the first lifter 27, the second lifter 28 collectively receives thesubstrates 9 from the substrate chuck 31 and collectively immerses thesubstrates 9 in the liquid chemical retained in the second liquidchemical tank 23. After the liquid chemical processing performed on thesubstrates 9 has completed, the second lifter 28 pulls the substrates 9up out of the second liquid chemical tank 23 and collectively immersesthe substrates 9 in the rinsing liquid retained in the second rinsingliquid tank 24. After the rinsing processing performed on the substrates9 has completed, the second lifter 28 pulls the substrates 9 up out ofthe second rinsing liquid tank 24. The substrate chuck 31 of the maintransport mechanism 3 collectively receives the substrates 9 from thesecond lifter 28 and moves to above the dry processing part 25.

The dry processing part 25 collectively receives the substrates 9 fromthe substrate chuck 31 and performs dry processing on the substrates 9at once. The dry processing involves, for example, supplying an organicsolvent (i.e., isopropyl alcohol) to the substrates 9 in areduced-pressure atmosphere and rotating the substrates 9 to remove theliquids on the substrates 9 by centrifugal force. After the dryprocessing performed on the substrates 9 has completed, the substratechuck 31 of the main transport mechanism 3 collectively receives theprocessed substrates 9 from the dry processing part 25 and moves in the−Y direction.

Then, a delivery chuck 73 of the delivery mechanism 7 illustrated inFIGS. 2 and 3 collectively receives the substrates 9 from the substratechuck 31 of the main transport mechanism 3 and moves in the −X directionto position the substrates 9 above the up-and-down holder 61 of thepusher 6. The up-and-down holder 61 of the pusher 6 moves upward andreceives the substrates 9 from the delivery chuck 73. The up-and-downholder 61 holds the plurality of (e.g., 50) substrates 9 aligned in theX direction in a vertical posture.

Next, the up-and-down holder 61 moves downward to transfer thesubstrates 9 in a vertical posture between the pusher 6 and the verticalholder 52. More specifically, among the substrates 9, the plurality of(e.g., 25) substrates 9 in the second substrate group are transferred tothe vertical holder 52 indicated by the dashed double-dotted line inFIG. 3. In other words, the batch of the first substrate group and thesecond substrate group is disassembled, and the first substrate groupand the second substrate group are separated from each other. Thehorizontal holder 51 and the vertical holder 52 of the posture changingmechanism 5 are rotated by 90 degrees in the clockwise direction in FIG.3. This rotation changes the posture of the substrates 9 in the secondsubstrate group at once from vertical to horizontal. These substrates 9are collectively held by the horizontal holder 51 while being stacked inthe Z direction in a horizontal posture. Then, the batch hand 41 of thecarry-in-and-out mechanism 4 receives the substrates 9 from thehorizontal holder 51 and carries the substrates 9 into the FOUP 95 onthe FOUP holder 1. The FOUP 95 to which the processed substrates 9 arecarried is replaced by a new FOUP 95.

When the posture changing mechanism 5 has changed the posture of thesubstrates 9 in the second substrate group from vertical to horizontalas described above, the up-and-down holder 61 that holds the pluralityof (e.g., 25) substrates 9 in the first substrate group is moved upward.The horizontal holder 51 and the vertical holder 52 that havetransferred the substrates 9 in the second substrate group to thecarry-in-and-out mechanism 4 are rotated by 90 degrees in thecounterclockwise direction in FIG. 3.

Then, the up-and-down holder 61 is again moved downward to transfer thesubstrates 9 in a vertical posture between the pusher 6 and the verticalholder 52. More specifically, the substrates 9 in the first substrategroup are transferred to the vertical holder 52 indicated by the dasheddouble-dotted line in FIG. 3. The horizontal holder 51 and the verticalholder 52 are again rotated by 90 degrees in the clockwise direction inFIG. 3. This rotation changes the posture of the substrates 9 in thefirst substrate group at once from vertical to horizontal. Thesesubstrates 9 are collectively held by the horizontal holder 51 whilebeing stacked in the Z direction in a horizontal posture. Then, thebatch hand 41 of the carry-in-and-out mechanism 4 receives thesubstrates 9 from the horizontal holder 51 and carries the substrates 9into the FOUP 95. Note that the posture changing mechanism 5 may firstreceive the first substrate group and then receive the second substrategroup in the operation of moving the substrates 9 from the pusher 6 tothe posture changing mechanism 5.

The posture changing mechanism 5 and the pusher 6 change the posture ofthe substrates 9 from horizontal to vertical or from vertical tohorizontal as described above under the control of the controller 100.In other words, the posture changing mechanism 5, the pusher 6, and thecontroller 100 constitute a posture changing device that changes theposture of the substrates 9 from one of horizontal and vertical posturesto the other posture.

While the substrate processing apparatus 10 illustrated in FIGS. 1 to 3performs processing on the substrates 9 having an approximatelydisc-like shape as described above, these substrates 9 may be warpedunder the influence of processing (i.e., pre-processing) performedbefore transport to the substrate processing apparatus 10. Althoughvarious types of warpage may occur in the substrates 9, a plurality ofsubstrates 9 housed in a single FOUP 95 are generally warped in the sameway. More specifically, when the positions of the notches 93 are used asa reference, the substrates 9 are in the same warped state. The warpedstate of the substrates 9 indicates information including theorientation of the warp in the substrates 9 (e.g., orientation in whichthe substrate is convex to the front surface side) and the magnitude ofthe warp in the substrates 9.

FIGS. 4 and 5 are perspective views illustrating examples of substrates9 in different warped states. The substrate 9 in FIG. 4 is curved in afirst radial direction K1 to one side in the thickness direction (i.e.,direction in which the substrate is convex upward in FIG. 4) with afirst curvature. The substrate 9 in FIG. 4 is also curved in a secondradial direction K2 orthogonal to the first radial direction K1 to theone side in the thickness direction (i.e., the same direction as thedirection of the curve in the first radial direction K1) with a secondcurvature greater than the first curvature.

The substrate 9 in FIG. 5 is curved in a first radial direction K3 toone side in the thickness direction (i.e., direction in which thesubstrate is convex upward in FIG. 5). The first radial direction K3 maybe different from the first radial direction K1 illustrated in FIG. 4.The substrate 9 in FIG. 5 is also curved in a second radial direction K4orthogonal to the first radial direction K3 to the other side in thethickness direction (i.e., direction opposite to the direction of thecurve in the first radial direction K3).

In the following description, the warped states of the substrates 9illustrated in FIGS. 4 and 5 are also respectively referred to as a“first warped state” and a “second warped state.” The distance in thethickness direction between lowest and highest points in the thicknessdirection of each warped substrate 9 in a horizontal posture is referredto as the “size in the thickness direction” of the substrate 9. When thesubstrate 9 is held in a vertical posture, the size in the thicknessdirection of the substrate 9 is equal to the distance in the thicknessdirection between the point of the substrate 9 closest to the one sidein the thickness direction and the point of the substrate 9 closest tothe other side in the thickness direction. When the substrate 9 is flatand not warped, the size in the thickness direction of the substrate 9is the same as the thickness of the substrate 9. The size in thethickness direction of a warped substrate 9 may be greater byapproximately 0.5 mm than the thickness of a flat substrate 9.

Next, the carry-in-and-out mechanism 4 of the substrate processingapparatus 10 will be described. FIG. 6 is a side view of thecarry-in-and-out mechanism 4. The carry-in-and-out mechanism 4 includesthe batch hand 41, the single-substrate hand 42, a hand advancing andretracting mechanism 44, a hand turning mechanism 45, and a handelevating mechanism 46. The hand advancing and retracting mechanism 44individually moves the batch hand 41 and the single-substrate hand 42 inthe horizontal direction. The hand turning mechanism 45 individuallyrotates the batch hand 41 and the single-substrate hand 42 in thehorizontal direction. The hand elevating mechanism 46 individually movesthe batch hand 41 and the single-substrate hand 42 in the up-downdirection.

FIG. 7 is a plan view of a substrate 9 held in a horizontal posture bythe batch hand 41. As illustrated in FIGS. 6 and 7, the batch hand 41includes a plurality of pairs of hand elements 43 that correspondrespectively to a plurality of substrates 9. These pairs of handelements 43 are aligned in the up-down direction (i.e., Z direction).Each pair of hand elements 43 supports the lower surface of eachsubstrate 9 held in horizontal posture, from the underside.

Each hand element 43 is a member that extends approximately in the Xdirection. More specifically, each hand element 43 is a plate-likemember having a generally strip shape in plan view. Each two handelements 432 are arranged side by side in the Y direction. The handelements 43 are support arms that support the substrates 9 held in ahorizontal posture from the underside. A substrate 9 is placed in ahorizontal posture on two hand elements 43 without being adsorbed by thebatch hand 41. The carry-in-and-out mechanism 4 is a transport mechanismfor transporting a plurality of substrates 9 that are placed in ahorizontal posture.

The two hand elements 43 have four supporters 47 that oppose the lowersurface of the peripheral portion of the substrate 9 in the up-downdirection. In FIG. 7, the four supporters 47 are enclosed with dasheddouble-dotted lines. The four supporters 47 are located at the positionsof intersections of the peripheral portion of the substrate 9 and thetwo hand elements 43 in plan view.

Next, a procedure for aligning the substrates 9 by the notch aligner 203and transporting the substrates 9 by the carry-in-and-out mechanism 4will be described with reference to the flowchart in FIG. 8. In thesubstrate processing apparatus 10 illustrated in FIG. 1, first,“warpage-and-notch-position information” is input to and stored in thestorage 101 in advance before the notch aligner 203 determines thecircumferential positions of a plurality of substrates 9 (step S11). Thewarpage-and-notch-position information includes a plurality ofcombinations of a warped state, which is common to a plurality ofsubstrates 9, and a notch position at which the substrates 9 in theabove warped state are in a proper posture when placed in a horizontalposture on the carry-in-and-out mechanism 4.

The notch position refers to the position in the circumferentialdirection of the notch 93 of the substrate 9. For example, a referencenotch position (i.e., 0° notch position) of the substrate 9 in ahorizontal posture may indicate a state in which the notch 93 is locatedat the position farthest on the +Y side from the two hand elements 43 asillustrated in FIG. 7. When the notch 93 is away in the circumferentialdirection from the reference position, an angle in the counterclockwisedirection between the reference position and the notch 93 when thesubstrate 9 is viewed from above (i.e., on the +Z side) is referred toas a “notch position.”

A combination of the warped state and the notch position included in thewarpage-and-notch-position information may be a combination of a code(e.g., numeric or symbol) that indicates the warped state of thesubstrate 9 illustrated in FIG. 4 or 5 and the angle that indicates thenotch position. The notch position refers to the position of the notch93 when the substrate 9 in the warped state illustrated in FIG. 4 or 5is rotated in the circumferential direction such that the lower surfaceof the substrate 9 comes into contact with the four supporters 47 of thepair of hand elements 43, while being placed in a horizontal posture onthe pair of hand elements 43.

FIGS. 9 and 10 are cross-sectional views illustrating a state in whichsubstrates 9 in the warped state illustrated in FIG. 4 are supported ina horizontal posture from the underside by the batch hand 41 (i.e.,placed on the batch hand 41). FIG. 9 illustrates a cross-section takenat a position along line IX-IX in FIG. 7, and FIG. 10 illustrates across-section taken at a position along line X-X in FIG. 7. In otherwords, FIGS. 9 and 10 illustrate cross-sections along the foursupporters 47 of the pair of hand elements 43. In FIGS. 9 and 10, it isassumed that the batch hand 41 simultaneously holds three substrates 9having notches located at different notch positions. The uppermostsubstrates 9 in FIGS. 9 and 10 show a state in which the notch 93 islocated at the reference position (i.e., 0° notch position). Thesubstrates 9 in the center in FIGS. 9 and 10 show a state in which thenotch is located at a 45° notch position. The lowermost substrates 9 inFIGS. 9 and 10 show a state in which the notch is located at a 90° notchposition.

In the example illustrated in FIGS. 9 and 10, when the notch is locatedat the 90° notch position, the lower surface of the substrate 9 placedon the pair of hand elements 43 is in contact with the four supporters47 of the pair of hand elements 43. When the notch is located at the 90°notch position, a distance D2 in the thickness direction between the topof the substrate 9 held in a horizontal posture and an area of contactof the peripheral portion of the substrate 9 with any supporter 47 isthe smallest. When the notch is located at the 0° notch position, thelower surface of the substrate 9 is also in contact with the foursupporters 47. When the notch is located at the 0° notch position, thedistance D2 is the next smallest after the distance D2 in the case wherethe notch is located at the 90° notch position.

On the other hand, when the notch is located at the 45° notch position,out of the two supporters 47 located on the +X side of the pair of handelements 43, the supporter 47 on the +Y side is in contact with thelower surface of the substrate 9, but the supporter 47 on the −Y side isnot in contact with the lower surface of the substrate 9. Out of the twosupporters 47 located on the −X side of the pair of hand elements 43,the supporter 47 on the −Y side is in contact with the lower surface ofthe substrate 9, but the supporter 47 on the +Y side is not in contactwith the lower surface of the substrate 9. When the notch is located atthe 45° notch position, the aforementioned distance D2 is the largest.

The warpage-and-notch-position information includes, for example, acombination of the code that indicates the warped state of the substrate9 illustrated in FIG. 4 and the 90° notch position. Thewarpage-and-notch-position information also includes, for example, acombination of the code that indicates the warped state of the substrate9 illustrated in FIG. 4 and the 0° notch position.

In the notch aligner 203 illustrated in FIG. 1, the warped state, whichis common to a plurality of substrates 9 conveyed into the substrateprocessing apparatus 10, is input and stored as input information aboutthe warped state in the storage 101 after step S11. This inputinformation may be a code that indicates the warped state of a pluralityof substrates 9.

Next, the controller 100 controls the substrate transport robot 204 sothat a first substrate 9 housed in the FOUP 95 placed on the FOUPplacement area 202 is conveyed into the notch aligner 203, and the notchaligner 203 starts rotating this substrate 9 (step S12). Then, thecontroller 100 controls the motor 203 a on the basis of the position ofthe notch 93, which is detected by the notch position sensor 203 b, theaforementioned input information, and the warpage-and-notch-positioninformation. Thus, the circumferential position of the notch 93 of thesubstrate 9 is changed and set to the desired position. Morespecifically, the notch position sensor 203 b detects the notch 93 ofthe rotating substrate 9, and the motor 203 a is stopped withpredetermined timing after the detection. The timing of stopping themotor 203 a is determined by the controller 100 on the basis of theaforementioned input information and the warpage-and-notch-positioninformation.

More specifically, the controller 100 extracts a notch position thatcorresponds to the warped state of the substrate 9 indicated by theinput information, from the above plurality of combinations included inthe warpage-and-notch-position information. Then, the substrate 9 isrotated until the position of the notch 93 of the substrate 9 matchesthe extracted notch position. When the position of the notch 93 hasmatched the extracted notch position, the rotation of the substrate 9 isstopped, and the circumferential position of the notch 93 of thesubstrate 9 is determined (step S13). The substrate 9 for which theposition of the notch 93 has been determined is returned to the FOUP 95on the FOUP placement area 202 by the substrate transport robot 204. Byrepeating the above processing in steps S12 and S13 for all of thesubstrates 9 housed in the FOUP 95 on the FOUP placement area 202, allof the substrates 9 housed in this FOUP 95 are sequentially aligned,with the position of the notch 93 of each substrate 9 matching the notchposition extracted by the controller 100. In the substrate processingapparatus 10, the notch aligner 203, the storage 101, and the controller100 constitute a substrate alignment apparatus that aligns a pluralityof substrates 9 each having a notch 93 in the peripheral portion. Notethat the FOUP 95 on the FOUP placement area 202 and the substratetransport robot 204 may also be regarded as part of the substratealignment apparatus.

The FOUP 95 that houses a plurality of substrates 9 aligned by thesubstrate alignment apparatus is moved from above the FOUP placementarea 202 to the FOUP holder 1 and placed on the FOUP holder 1 by thesecond FOUP transfer robot 207. Thereafter, the substrates 9 aretransferred in a horizontal posture from the FOUP 95 to thecarry-in-and-out mechanism 4 illustrated in FIG. 6, and placed on thecarry-in-and-out mechanism 4. More specifically, each substrate 9 isplaced on each pair of hand elements 43 of the batch hand 41. The lowersurface of each substrate 9 placed on each pair of hand elements 43 isin contact with the aforementioned four supporters 47, because thecircumferential position of the notch 93 of the substrate 9 is alreadyset to the desired notch position by the notch aligner 203 in step S13as described above. This configuration prevents or suppresses theoccurrence of rattling or misalignment of each substrate 9 duringtransport of the substrate 9 by the carry-in-and-out mechanism 4, andthereby enables stable transport of the substrates 9. In the substrateprocessing apparatus 10, the carry-in-and-out mechanism 4, the notchaligner 203, the controller 100, and the storage 101 constitute asubstrate transporter that transports the substrates 9. Note that theFOUP 95 on the FOUP placement area 202 and the substrate transport robot204 may also be regarded as part of the substrate transporter. Thesecond FOUP transfer robot 207 may also be regarded as part of thesubstrate transporter.

FIG. 11 is a cross-sectional view of a hand element 43 and a substrate9, taken at a position along line XI-XI in FIG. 7. In the exampleillustrated in FIG. 11, the substrate 9 is convex upward between the twosupporters 47 of the hand element 43 and vertically upward of the handelement 43 (i.e., on the +Z side). Although not shown, the substrate 9is also convex upward between the two supporters 47 of the other handelement 43 and vertically upward of the other hand element 43.

The plurality of substrates 9 placed in a horizontal posture on thebatch hand 41 are transported to the position changing mechanism 5 bydriving the hand turning mechanism 45 and the hand advancing andretracting mechanism 44 (step S14). The hand elevating mechanism 46 mayalso be driven as necessary for transport of the substrates 9. FIG. 12illustrates a detailed procedure performed in step S14. In step S14,first, the movement of the batch hand 41 is started and accelerated(step S141). When the batch hand 41 approaches the position changingmechanism 5, the batch hand 41 is deaccelerated, and the movement of thebatch hand 41 is stopped (step S142).

During transport of the substrate 9 in step S14, the controller 100controls the carry-in-and-out mechanism 4 to control the acceleration atthe time of starting and stopping the movement of the carry-in-and-outmechanism 4. More specifically, the controller 100 controls the handadvancing and retracting mechanism 44 on the basis of the aforementionedinput information (i.e., information indicating the warped state that iscommon to a plurality of substrates 9) stored in the storage 101 so asto determine the acceleration at the time of starting the movement ofthe batch hand 41 in step S141. For example, when the distance D2estimated from the above input information is greater than apredetermined threshold value, it is determined that the stability ofthe substrates 9 on the batch hand 41 may deteriorate during transport,and accordingly, the acceleration at the time of starting the movementis set to be lower than the normal acceleration. The acceleration at thetime of stopping the movement of the batch hand 41 in step S142 is alsoset in the same manner. This improves the stability of transport of thesubstrates 9 by the carry-in-and-out mechanism 4. In thecarry-in-and-out mechanism 4, the controller 100 may also control theacceleration at the time of starting and stopping the movement of thehand turning mechanism 45 or the hand elevating mechanism 46 on thebasis of the warped state of the substrates 9, in the same manner as inthe case of the hand advancing and retracting mechanism 44.

As described above, the aforementioned substrate transporter includesthe carry-in-and-out mechanism 4 that is a transport mechanism, thenotch aligner 203 that is a notch-position changing mechanism, thestorage 101, and the controller 100. The carry-in-and-out mechanism 4transports substrates 9 placed in a horizontal posture. The notchaligner 203 rotates substrates 9 that are to be placed on thecarry-in-and-out mechanism 4, in the circumferential direction to changethe circumferential positions of the notches 93 provided in theperipheral portions of the substrates 9. The storage 101 stores thewarpage-and-notch-position information. The warpage-and-notch-positioninformation includes a plurality of combinations of the warped state ofthe substrates 9 and the notch position at which the substrates 9 inthis warped state are in a proper posture when placed on thecarry-in-and-out mechanism 4. The controller 100 controls the notchaligner 203. The carry-in-and-out mechanism 4 includes four supporters47 that oppose the lower surface of the peripheral portion of eachsubstrate 9.

In the substrate transporter, the controller 100 controls the notchaligner 203 on the basis of the input information that is input aboutthe warped state of the substrates 9 and the warpage-and-notch-positioninformation, so as to determine the circumferential positions of thenotches 93 of the substrates 9. Thus, the lower surface of eachsubstrate 9 placed on the carry-in-and-out mechanism 4 comes intocontact with the four supporters 47 of the carry-in-and-out mechanism 4.As a result, it is possible to prevent or suppress the occurrence ofrattling or misalignment of the substrates 9 during transport of thesubstrates 9 by the carry-in-and-out mechanism 4, and thereby enablestable transport of the substrates 9.

In the substrate transporter, the carry-in-and-out mechanism 4 includestwo hand elements 43. Each of the two hand elements 43 has twosupporters 47 provided thereon among the aforementioned four supporters47. A substrate 9 placed on the carry-in-and-out mechanism 4 is convexupward between the two supporters 47 on each hand element 43 andvertically upward of each hand element 43. Thus, the lower surface ofthe substrate 9 can suitably come into contact with the two supporters47 of each hand element 43. As a result, it is possible to improve thestability of transport of the substrates 9 by the carry-in-and-outmechanism 4.

In the substrate transporter, the controller 100 controls thecarry-in-and-out mechanism 4 on the basis of the warped state of thesubstrates 9 so as to control the acceleration at the time of startingand stopping the movement of the carry-in-and-out mechanism 4. Thus, asdescribed above, it is possible to improve the stability of transport ofthe substrates 9 by the carry-in-and-out mechanism 4.

The aforementioned substrate transporter may transport a singlesubstrate 9 or may transport a plurality of substrates 9 at once. Whenthe substrate transporter transports a plurality of substrates 9 atonce, the carry-in-and-out mechanism 4 also transports other substrates9 along with the aforementioned single substrate 9. The notch aligner203 sequentially rotates the other substrates 9 and the signal substrate9 in the circumferential direction to change the circumferentialpositions of the notches 93 provided in the peripheral portions of theother substrates 9 in the same manner as in the case of the singlesubstrate 9. The carry-in-and-out mechanism 4 includes another foursupporters 47 that oppose the lower surface of each of the othersubstrates 9. The lower surface of the peripheral portion of each of theother substrates 9 placed on the carry-in-and-out mechanism 4 comes intocontact with the other four supporters 47 of the carry-in-and-outmechanism 4. This configuration prevents or suppresses the occurrence ofrattling or misalignment of the substrates 9 during transport of thesubstrates 9 by the carry-in-and-out mechanism 4. As a result, it ispossible to stably transport the substrates 9. The controller 100controls the carry-in-and-out mechanism 4 on the basis of the warpedstate of the substrates 9 so as to control the acceleration at the timeof starting and stopping the movement of the carry-in-and-out mechanism4. This improves the stability of transport of the substrates 9 by thecarry-in-and-out mechanism 4.

The substrate transporter and the substrate processing apparatus 10described above may be modified in various ways.

The notch aligner 203 may be a device having any of various types ofstructures as long as it is capable of changing the circumferentialpositions of the notches 93 by rotating the substrates 9 in thecircumferential direction. For example, the notch aligner 203 may be amechanism for rotating a plurality of substrates 9 simultaneously in thecircumferential direction to determine the circumferential positions ofthe notches 93 of the substrates 9. That is, the motor 203 a of thenotch aligner 203 may be a rotator that rotates a plurality ofsubstrates 9 either sequentially or simultaneously in thecircumferential direction. In either case, the carry-in-and-outmechanism 4 is capable of stably transporting a plurality of substrates9 as described above. The notch aligner 203 may also be a mechanism forrotating substrates 9 in a vertical posture either sequentially orsimultaneously in the circumferential direction to change thecircumferential orientations of the substrates 9. Moreover, the notchaligner 203 may cause the notches 93 of the substrates 9 to engage witha predetermined engagement shaft in order to stop the rotation of thesubstrates 9.

For example, the substrate transporter (i.e., the carry-in-and-outmechanism 4, the notch aligner 203, the storage 101, and the controller100) does not necessarily have to control the acceleration of thecarry-in-and-out mechanism 4 in step S14 as long as the notch aligner203 determines the positions of the notches 93 and thereby the lowersurface of each substrate 9 placed on the carry-in-and-out mechanism 4comes into contact with the four supporters 47 of the carry-in-and-outmechanism 4.

The substrate processing apparatus 10 does not necessarily have todetermine the positions of notches 93 before transport of substrates 9.In the case where the determination of the positions of notches 93 isomitted, the lower surface of each substrate 9 placed on thecarry-in-and-out mechanism 4 does not necessarily have to come intocontact with all of the four supporters 47 of the carry-in-and-outmechanism 4. In this case, the notch aligner 203 may be omitted, and theaforementioned substrate transporter may include only thecarry-in-and-out mechanism 4 that is a transport mechanism and thecontroller 100. The carry-in-and-out mechanism 4 transports a single ora plurality of substrates 9 placed in a horizontal posture. Thecontroller 100 controls the carry-in-and-out mechanism 4 on the basis ofthe warped state of the single or plurality of substrates 9 so as tocontrol the acceleration at the time of starting and stopping themovement of the carry-in-and-out mechanism 4. More specifically, forexample when it is determined on the basis of the warped state of asubstrate 9 that the lower surface of a substrate 9 is not in contactwith one or two of the four supporters 47, the acceleration at the timeof starting and stopping the movement of the carry-in-and-out mechanism4 is set to be lower than the normal acceleration. This configurationprevents or suppresses the occurrence of rattling or misalignment of thesingle or plurality of substrates 9 during transport by thecarry-in-and-out mechanism 4, as described above. As a result, it ispossible to stably transport the single or plurality of substrates 9.

The aforementioned substrate transporter may be used as a deviceindependent of the other configuration of the substrate processingapparatus 10. Alternatively, the substrate transporter may beincorporated into and used in any of various apparatuses other than theaforementioned substrate processing apparatus 10.

The substrate processing apparatus 10 may be used to process glasssubstrates used in display devices such as liquid crystal displays,plasma displays, and field emission displays (FEDs), instead ofsemiconductor substrates. The substrate processing apparatus 10 may alsobe used to process other substrates such as optical disk substrates,magnetic disk substrates, magneto-optical disk substrates, photomasksubstrates, ceramic substrates, and solar-cell substrates.

The configurations of the above-described preferred embodiments andvariations may be appropriately combined as long as there are no mutualinconsistencies.

While the invention has been shown and described in detail, theforegoing description is in all aspects illustrative and notrestrictive. It is therefore to be understood that numerousmodifications and variations can be devised without departing from thescope of the invention. This application claims priority benefit under35 U.S.C. Section 119 of Japanese Patent Application No. 2016-190861filed in the Japan Patent Office on Sep. 29, 2016, the entire disclosureof which is incorporated herein by reference.

REFERENCE SIGNS LIST

4 Carry-in-and-out mechanism

9 Substrate

43 Hand element

47 Supporter

93 Notch

100 Controller

101 Storage

203 Notch aligner

S11 to S14, S141, S142 Step

The invention claimed is:
 1. A substrate transporter comprising: atransport mechanism for transporting a substrate that is placed in ahorizontal posture, said transport mechanism including a support armthat supports said substrate, and four supporters that are provided onsaid support arm so as to oppose a lower surface of a peripheral portionof said substrate; a notch-position changing mechanism for rotating saidsubstrate that is to be placed on said transport mechanism, in acircumferential direction to change a position in said circumferentialdirection of a notch that is provided in said peripheral portion of saidsubstrate; a storage for storing warpage-and-notch-position informationin advance of placing said substrate on said transport mechanism;wherein said warpage-and-notch-position information includes a pluralityof pieces of combination information, each said piece of combinationinformation being a combination of a warped state of said substrate anda notch position at which said substrate in said warped state is held inan optimal posture where said lower surface of said peripheral portionof said substrate and said four supporters of said transport mechanismare brought into contact with each other when said substrate is placedon said transport mechanism, said plurality of pieces of combinationinformation being obtained by combining a plurality of warped stateswith a plurality of notch positions respectively, wherein said substratein a warped state corresponding to a respective notch position is heldin said optimal posture at said respective notch position; and acontroller for controlling said notch-position changing mechanism,wherein said controller extracts a notch position from saidwarpage-and-notch-position information, said notch positioncorresponding to an input warped state of said substrate indicated byinput information that is input about the warped state of saidsubstrate, and said lower surface of said peripheral portion of saidsubstrate that is placed on said transport mechanism and said foursupporters of said transport mechanism are brought into contact witheach other by said controller controlling said notch-position changingmechanism on the basis of said notch position extracted from saidwarpage-and-notch-position information to determine said position insaid circumferential direction of said notch of said substrate forproviding said optimal posture.
 2. The substrate transporter accordingto claim 1, wherein said transport mechanism includes two hand elements,on each of which two supporters among said four supporters are provided,and said substrate that is placed on said transport mechanism is convexupward between said two supporters of each hand element and verticallyupward of said each hand element.
 3. The substrate transporter accordingto claim 2, wherein said transport mechanism transports anothersubstrate along with said substrate, said notch-position changingmechanism rotates said another substrate and said substrate eithersequentially or simultaneously in said circumferential direction todetermine a position in said circumferential direction of a notch thatis provided in a peripheral portion of said another substrate, in thesame manner as in the case of said substrate, said transport mechanismincludes another four supporters that oppose a lower surface of saidperipheral portion of said another substrate, and said lower surface ofsaid another substrate that is placed on said transport mechanism comesinto contact with said another four supporters of said transportmechanism.
 4. The substrate transporter according to claim 1, whereinsaid transport mechanism transports another substrate along with saidsubstrate, said notch-position changing mechanism rotates said anothersubstrate and said substrate either sequentially or simultaneously insaid circumferential direction to determine a position in saidcircumferential direction of a notch that is provided in a peripheralportion of said another substrate, in the same manner as in the case ofsaid substrate, said transport mechanism includes another foursupporters that oppose a lower surface of said peripheral portion ofsaid another substrate, and said lower surface of said another substratethat is placed on said transport mechanism comes into contact with saidanother four supporters of said transport mechanism.
 5. The substratetransporter according to claim 1, wherein said substrate is curved in afirst radial direction to one side in a thickness direction of saidsubstrate with a first curvature, and said substrate is curved in asecond radial direction orthogonal to said first radial direction tosaid one side in said thickness direction with a second curvaturegreater than said first curvature.
 6. The substrate transporteraccording to claim 1, wherein said substrate is curved in a first radialdirection to one side in a thickness direction of said substrate, andsaid substrate is curved in a second radial direction orthogonal to saidfirst radial direction to the other side in said thickness direction. 7.A substrate transport method comprising: a) storingwarpage-and-notch-position information in advance of placing saidsubstrate on a transport mechanism that includes a plurality of piecesof combination information, each said piece of combination informationbeing a combination of a warped state of a substrate and a notchposition, for placing said substrate in a horizontal posture on saidtransport mechanism including a support arm that supports saidsubstrate, and four supporters that are provided on said support arm soas to oppose a lower surface of a peripheral portion of said substrate,said notch position being a position at which said substrate in saidwarped state is held in an optimal posture where said lower surface ofsaid peripheral portion of said substrate and said four supporters ofsaid transport mechanism are brought into contact with each other whensaid substrate is placed on said transport mechanism, said plurality ofpieces of combination information being obtained by combining aplurality of warped states with a plurality of notch positionsrespectively, wherein said substrate in a warped state corresponding toa respective notch position is held in said optimal posture at saidrespective notch position; b) rotating said substrate in acircumferential direction to determine a position in saidcircumferential direction of a notch that is provided in said peripheralportion of said substrate; and c) placing said substrate in a horizontalposture on said transport mechanism and transporting said substrate,wherein in said operation b), a notch position is extracted from saidwarpage-and-notch-position information, said notch positioncorresponding to an input warped state of said substrate indicated byinput information that is input about the warped state of saidsubstrate, and in said operation b), the position in saidcircumferential direction of said notch of said substrate is determinedon the basis of said notch position extracted from saidwarpage-and-notch-position information, as a result of which said lowersurface of said peripheral portion of said substrate that is placed onsaid transport mechanism comes into contact with said four supporters ofsaid transport mechanism in said operation c).